Biological parameters for quality evaluation of allografts from the Brazilian National Institute of Traumatology and Orthopedics tissue bank.

Bone allografts are clinically used in a variety of surgical procedures, and tissue banks are responsible for harvesting, processing, quality testing, storing, and delivering these materials for transplantation. In tissue banks, the bone is processed for the removal of all organic content, remaining only the tissue structure (scaffold). However, several studies have shown that even after using different processing methods, viable cells, functional proteins, and DNA may still persist in the tissue, which constitute the main causes of graft rejection. Therefore, the objective of this study was to establish techniques and biological parameters for quality validation of allografts. To this end, we propose the use of 3 combined methods such as microscopy, histology, and molecular biology techniques to evaluate the quality of allografts harvested and processed by the Brazilian National Institute of Traumatology and Orthopedics (INTO) tissue bank according to the donation criteria of the Brazilian National Health Surveillance Agency and the Brazilian National Transplant System. Bone fragments from different processing stages showed no viable cells on histology, an intact extracellular matrix on scanning electron microscopy, and gradual reduction in DNA amount. Different techniques were used to demonstrate the quality of allografts produced by the INTO tissue bank and to establish biological parameters for ensuring the safety and quality of these products. Future studies need to be undertaken to assess and validate the efficacy of the decellularization process in larger bone grafts with diverse architectural configurations.

A new option for bone regeneration: a rapid methodology for cellularization of allograft with human bone marrow stromal cells with in vivo bone-forming potential.

The treatment of severe musculoskeletal injuries, such as loss of bone tissue and consolidation disorders, requires bone transplantation, and the success of this bone reconstruction depends on the grafts transplant's osteogenic, osteoconductive, and osteoinductive properties. Although the gold standard is autograft, it is limited by availability, morbidity, and infection risk. Despite their low capacity for osteoinduction and osteogenesis, decellularized bone allografts have been used in the search for alternative therapeutic strategies to improve bone regeneration. Considering that bone marrow stromal cells (BMSCs) are responsible for the maintenance of bone turnover throughout life, we believe that associating BMSCs with allograft could produce a material that is biologically similar to autologous bone graft. For this reason, this study evaluated the osteogenic potential of bone allograft cellularized with BMSCs. First, BMSC was characterized and allograft decellularization was confirmed by histology, scanning electron microscopy, and DNA quantification. Subsequently, the BMSCs and allografts were associated and evaluated for adhesion, proliferation, and in vitro and in vivo osteogenic potential. We demonstrated that, after 2 hours, BMSCs had already adhered to the surface of allografts and remained viable for 14 days. In vitro osteogenic assays indicated increased osteogenic potential of allografts compared with beta-tricalcium phosphate (ß-TCP). In vivo transplantation assays in immunodeficient mice confirmed the allograft's potential to induce bone formation, with significantly better results than ß-TCP. Finally, our results indicate that allograft can provide structural support for BMSC adhesion, offering a favorable microenvironment for cell survival and differentiation and inducing new bone formation. Taken together, our data indicate that this rapid methodology for cellularization of allograft with BMSCs might be a new therapeutic alternative in regenerative medicine and bone bioengineering.

Comprehensive Retrospective Analysis of Corneal Donor Characteristics at the National Institute of Traumatology and Orthopedics Eye Bank (2013-2021).

BACKGROUND: Corneal transplantation success depends on good practices in tissue selection and preservation. This study aimed to assess the relationship between the time from the donor's death to the end of processing and corneal cellularity provided by the Eye Bank. METHODS: This was a retrospective study of 839 donor records (2013-2021) from the Eye Bank of the National Institute of Traumatology and Orthopedics, totaling 1445 corneas. Donors were classified based on cellularity (≤2000 and >2000 cells/mm2) and laterality. The dependent variable was cellularity in the right eye (RE) and left eye (LE), categorized into ≤2000 and >2000 cells/mm2 groups. Independent variables included sex, age, cause of death, and Δ-death. The statistical software SPSS 26.0 (IBM SPSS, Inc, Armonk, NY, United States) was used, and P < 0.05 was considered significant. RESULTS: Among 839 donors, most were male (58.2%) and ≥60 years old (36.5%). Brain death (BD) was the primary cause of death (66.2%). A time from the donor's death to the end of processing interval of ≥10 hours occurred in 35.6% of cases. Cellularity >2000 cells/mm2 was similar for the RE (94.5%) and LE (93.9%). Age showed statistical significance (P < 0.001) in both eyes, with cellularity decreasing for donors ≥60 years. In BD cases, higher cellularity was observed in the LE (P < 0.001; 70.8%). A time from the donor's death to the end of processing interval and cellularity comparison showed relevance for the LE (P = 0.03) but no association for the RE. CONCLUSIONS: Corneal cellularity decreased with increasing donor age. Significant differences in Δ-death were associated with cellularity, BD, and right and left cornea.

Harvest, Transport, and Storage of Fresh Humeral Head Osteochondral Allograft: Step-by-Step Protocol.

Articular cartilage defects are not common in the glenohumeral joint and are mostly found in patients after shoulder trauma, in patients with recurrent instability, or in patients who underwent previous surgical treatment. Articular cartilage defects lead to pain and loss of motion, consequently causing shoulder function impairment and reducing quality of life. In young patients, the use of osteochondral allografts for the treatment of humeral head defects may avoid well-known complications of shoulder arthroplasty. The goal of this Technical Note is to describe a step-by-step protocol for the harvesting, transport, and preservation of fresh humeral head osteochondral tissue for use in allograft transplantation.

Protocol for Harvest, Transport and Storage of Human Osteochondral Tissue.

Objective To elaborate a protocol for the harvest, transport, and preservation of human osteochondral tissue for use in tissue banks (TBs). Methods Osteochondral fragments measuring 2 cm 3 of 5 corpse donors aged between 15 and 45 years old were analyzed. The samples were stored in cell preservation medium containing: human albumin, Iscove's and vancomycin preserved at 4°C. The concentration of proteoglycans in the extracellular medium was quantified by the use of Safranin-O, while tissue structural analysis was assessed by histological study with hematoxylin-eosin stained slides. The images obtained were analyzed according to the histological scores of Mankin and the score proposed by the OsteoArthritis Research Society International. The samples were analyzed with 0, 15, 30 and 45 days of preservation. Results The osteochondral fragments studied showed a progressive decrease in proteoglycan concentration with increased preservation time. After 30 days of preservation, structural changes were identified with discontinuity of the cartilage surface layer. According to the results obtained by the Mankin score, there was a statistically significant difference between 15 and 30 days of tissue preservation. Conclusion The protocol described defined knee transport immersed in Lactated Ringer at a controlled temperature of 10° C until its arrival at the TB. After processing, the preservation solution was composed of Iscove's serum-free cell culture medium supplemented with 10% human albumin and 100 µg/ml vancomycin. The tissue was preserved at a temperature of 4°C until the moment of transplantation characterizing the fresh preservation.

Protocol for Harvest, Transport and Storage of Human Osteochondral Tissue / Protocolo para captação, transporte e preservação de tecido osteocondral humano

Abstract Objective To elaborate a protocol for the harvest, transport, and preservation of human osteochondral tissue for use in tissue banks (TBs). Methods Osteochondral fragments measuring 2 cm3 of 5 corpse donors aged between 15 and 45 years old were analyzed. The samples were stored in cell preservation medium containing: human albumin, Iscove's and vancomycin preserved at 4ºC. The concentration of proteoglycans in the extracellular medium was quantified by the use of Safranin-O, while tissue structural analysis was assessed by histological study with hematoxylin-eosin stained slides. The images obtained were analyzed according to the histological scores of Mankin and the score proposed by the OsteoArthritis Research Society International. The samples were analyzed with 0, 15, 30 and 45 days of preservation. Results The osteochondral fragments studied showed a progressive decrease in proteoglycan concentration with increased preservation time. After 30 days of preservation, structural changes were identified with discontinuity of the cartilage surface layer. According to the results obtained by the Mankin score, there was a statistically significant difference between 15 and 30 days of tissue preservation. Conclusion The protocol described defined knee transport immersed in Lactated Ringer at a controlled temperature of 10º C until its arrival at the TB. After processing, the preservation solution was composed of Iscove's serum-free cell culture medium supplemented with 10% human albumin and 100 µg/ml vancomycin. The tissue was preserved at a temperature of 4ºC until the moment of transplantation characterizing the fresh preservation.

Resumo Objetivo Elaborar um protocolo para a captação, transporte e preservação de tecido osteocondral humano para utilização em banco de tecidos (BT). Métodos Foram analisados fragmentos osteocondrais com dimensão de 2 cm3 de 5 doadores cadáveres com idades entre 15 e 45 anos. As amostras foram armazenadas em meio de preservação celular contendo: albumina humana, Iscove's e vancomicina preservados à temperatura de 4ºC. A concentração de proteoglicanos no meio extracelular foi quantificada pelo uso de Safranina-O, enquanto a análise estrutural do tecido foi avaliada através de estudo histológico com lâminas coradas em hematoxilina-eosina. As imagens obtidas foram analisadas segundo os escore histológicos de Mankin e o escore proposto pela OsteoArthritis Research Society International. As amostras foram analisadas com 0, 15, 30 e 45 dias de preservação. Resultados Os fragmentos osteocondrais estudados apresentaram diminuição progressiva na concentração de proteoglicanos com o aumento do tempo de preservação. Após 30 dias de preservação, foram identificadas alterações estruturais com descontinuidade da camada superficial da cartilagem. Segundo os resultados obtidos pelo escore de Mankin, houve diferença com significância estatística entre 15 e 30 dias de preservação do tecido. Conclusão O protocolo descrito definiu o transporte de joelho em bloco imerso em Ringer Lactato em temperatura controlada a 10ºC até sua chegada ao BT. Após o processamento, a solução de preservação foi composta por meio de cultura celular sem soro Iscove's suplementado com albumina humana a 10% e vancomicina 100 µg/mL. O tecido foi preservado à temperatura de 4ºC até o momento do transplante caracterizando a preservação a fresco.

Diretrizes para avaliação e validação do potencial doador de órgãos em morte encefálica / Guidelines for the assessment and acceptance of potential brain-dead organ donors

RESUMO O transplante de órgãos é a única alternativa para muitos pacientes portadores de algumas doenças terminais. Ao mesmo tempo, é preocupante a crescente desproporção entre a alta demanda por transplantes de órgãos e o baixo índice de transplantes efetivados. Dentre as diferentes causas que alimentam essa desproporção, estão os equívocos na identificação do potencial doador de órgãos e as contraindicações mal atribuídas pela equipe assistente. Assim, o presente documento pretende fornecer subsídios à equipe multiprofissional da terapia intensiva para o reconhecimento, a avaliação e a validação do potencial doador de órgãos.

ABSTRACT Organ transplantation is the only alternative for many patients with terminal diseases. The increasing disproportion between the high demand for organ transplants and the low rate of transplants actually performed is worrisome. Some of the causes of this disproportion are errors in the identification of potential organ donors and in the determination of contraindications by the attending staff. Therefore, the aim of the present document is to provide guidelines for intensive care multi-professional staffs for the recognition, assessment and acceptance of potential organ donors.

Doação e fila de transplante de córnea no Estado do Rio de Janeiro / Donation and waiting list for corneal transplantation in the State of Rio de Janeiro

O presente trabalho objetiva descrever o processo de doação, captação, fila de espera e transplante de órgãos e tecidos como uma das políticas de saúde no Brasil e no Estado do Rio de Janeiro, com ênfase nos procedimentos relativos aos transplantes de córnea. A baixa notificação de possíveis doadores e a alta taxa de negativa familiar na doação associado ao insuficiente número de córneas disponibilizadas por Banco de Olhos são os principais fatores que limitam o aumento do número dos transplantes de córnea no Brasil. A criação do Banco de Olhos do Rio de Janeiro, associado a politicas que estimulam o aumento da notificação e captação de córneas visa diminuir a fila de espera para transplante de córnea no Estado.

This paper aims to describe the process of organ and tissue donation, tissue harvesting, queue and transplants as a health policy in Brazil and in the State of Rio de Janeiro, with emphasis on procedures for corneal transplantation. The low reporting of possible donors associated with a high rate of negative family in donation, associated with the insufficient number of corneas provided by Eye Banks are the main factors limiting the increase in the number of corneal transplants in Brazil. The creation of the Rio de Janeiro Eye Bank associated with policies that encourage increased reporting and collection of corneas aims to reduce the waiting list for corneal transplantation in Rio de Janeiro State.

Axonal and extracellular matrix responses to experimental chronic nerve entrapment.

We have analyzed the ultrastructural and histopathological changes that occur during experimental chronic nerve entrapment, as well as the immunohistochemical expression of chondroitin sulfate proteoglycan (CSPG). Adult hamsters (n = 30) were anesthetized and received a cuff around the right sciatic nerve. Animals survived for varying times (5 to 15 weeks) being thereafter perfused transcardially with fixative solutions either for immunohistochemical or electron microscopic procedures. Experimental nerves were dissected based upon the site of compression (proximal, entrapment and distal). CSPG overexpression was detected in the compressed nerve segment and associated with an increase in perineurial and endoneurial cells. Ultrastructural changes and data from semithin sections were analyzed both in control and compressed nerves. We have observed endoneurial edema, perineurial and endoneurial thickening, and whorled cell-sparse pathological structures (Renaut bodies) in the compressed nerves. Morphometrical analyses of myelinated axons at the compression sites revealed: (a) a reduction both in axon sectional area (up to 30%) and in myelin sectional area (up to 80%); (b) an increase in number of small axons (up to 60%) comparatively to the control group. Distal segment of compressed nerves presented: (a) a reduction in axon sectional area (up to 60%) and in myelin sectional area (up to 90%); (b) a decrease in axon number (up to 40%) comparatively to the control data. In conclusion, we have shown that nerve entrapment is associated with a local intraneural increase in CSPG expression, segmental demyelination, perineurial and endoneurial fibrosis, and other histopathological findings.